Toshiba CF19G32 CRT RGB mod
Captured from RGB modded NES
You can die doing this! So read carefully! CRT TV is not a toy. Do not open a CRT TV. If you don't have any prior knowledge about handling high voltage devices, this guide is not for you. CRT TV contains high enough voltage (20,000+ V) and current to be deadly, even when it is turned off.
Plan of attack
Sometimes it is nice to know the theory behind the mod. I have put this on a separate page. This shows how the various resistor values are calculated.
- Manufactured: Made in Thailand, May 2001
- NTSC, 60 Hz
- Chassis: CF19G32
- Tube: Toshiba A48KZL70X
- OSD Chip: TMP87CM34BN
- Jungle Chip: TA1223AN
Get hold of the schematics for your TV. Understand where the RGB and Fast Blanking signals go from OSD to the Jungle (Chroma) chip.
Jungle Chip ^
OSD Chip ^
Mux Diagram ^
Performing the mod
STEP 1: Remove the following components
Remove the three 1.2 kΩ, RGB resistors to ground
STEP 2: Remove jumpers and install diodes
Remove jumpers 035, 036 and 037. Install diodes (1N4148) in those locations instead. Pay attention to the direction of the diodes. This will prevent the current from going into the OSD, creating a reflection in signal, that causes interference.
STEP 3: Connect RGBs
Points where the R, G, B and Blank (brown) wires should be connected. Ignore the colors of the wires. I used a shielded wire for this mod. R, G, B wires were not individually shielded. However, there were absolutely no intereference noticed.
STEP 4: Hook up blanking and Audio
Routed the wires from the top of the board to the bottom side. Some holes were covered with solder. Removed it to expose the holes and routed the wires through them.
Purple and black wires were routed to ground. Yellow wire to composite input pin. White wire to audio left. Gray wire to audio right.
STEP 5: Build your mux circuit
Below mod uses the RGB mux board. This is optional, but will make your mod easier and stable. You can also create the circuit presented in the schematics above without the board. Please also checkout the precalculated resistor values.
I had to use a RGB tuner gadget I made to find the right balance for RGB termination. It was found using a 150Ω to 180Ω resistor gave the best vibrancy of colors.
|RGB Mux Board Notes
|RGB inline resistors
|RA22, RA23, RA24
|RR90, RR91, RR92 (removed from chassis)
|R4, R5, R6 (measured using the tuner)
|R7, R8 (1 kΩ resistor present on the board)
|R9 (CRT internal 5.6kΩ resistor for 2.5V)
|R10 (CRT internal grounding resistor is used)
|R12 (75Ω terminated in the CRT)
STEP 6: Attach the female SCART connector to TV
Creating a SCART cutout and mounting it is an art. I have a dedicated section for it.
SCART connector mounted
SNES Metroid - OSD Overlay
SEGA Genesis - Sonic
XBOX - UnleashX
SNES - Super Mario World
SNES - Super Mario World
PS2 - GTA San Andreas
NES - Donkey Kong
240p - Grid
Mute on the remote and press
Menu on the CRT to enter Service Mode
Press Menu again on the CRT for options. CH buttons to change option. VOL buttons to increase/decrease values
- AUD - 00H
- HPOS - 19H
- VPOS - 05H
- HIT - 1DH
- RCUT - 7CH (default)
- GCUT - 42H (default)
- BCUT - 6AH (default)
- GRDV - 6DH (default)
- BDRV - 82H (default)
- BRTC - 38H
Recall on the remote and press
Menu on the CRT to enter Design Mode